June 4th was the 24th anniversary of a government crackdown on pro-democracy protesters in Beijing when troops with tanks and assault rifles forcibly suppressed student protesters who had set up camp in Tiananmen Square.

In China, Internet searches for "Tiananmen Square" turn up nothing. There’s very little mention of it on Sina Weibo -- China's Twitter-equivalent -- where people are increasingly turning to speak their minds. Even in an age when the Chinese are finding their voices, silence is enforced on the topic, officially and electronically:

For a few days, previously blocked searches suddenly began to produce innocuous, carefully selected results.

When stories come up about the anniversary on news channels like CNN and BBC (available on satellite TV), screens go black -- returning only with coverage of benign topics.

Despite censorship and downplay, interest remains high among social media users. Weibo users posted comments noting the arrival of dark clouds over Beijing around noon on Tuesday. Another user adds: “This seems to mean that something happened in the past, but I can’t search for it.”

Anyone in China can get around the "Great Firewall" by shelling out roughly $6 per month for a "VPN," or "virtual private network," which allows a web user to connect to the Internet as though he or she is in another country.

Thank You

By registering you become a member of the CBS Interactive family of sites and you have read and agree to the Terms of Use, Privacy Policy and Video Services Policy. You agree to receive updates, alerts and promotions from CBS and that CBS may share information about you with our marketing partners so that they may contact you by email or otherwise about their products or services.
You will also receive a complimentary subscription to the ZDNet's Tech Update Today and ZDNet Announcement newsletters. You may unsubscribe from these newsletters at any time.